Control system



Nov. 9 ,1926. v I 1,606,448

c. F. ROBINSCN CONTROL SYSTEM Filed Dec. 29, 1921 E a 4845/ Jo 3/WITNESS 3 INVENTOR Char/as l Fob/neon.-

F 545 IQ 34 ATTORNEYS Patented Nov. 9, 1926.

CHARLES F. ROBINSON, OF'SAN FRANCISCO, CALIFORNIA.

CONTROL SYSTEM.

Application filed December 29, 1921. Serial No. 525,578.

The primary object of the present invention is to provide a remotecontrol valve adapted to operate machinery actuated by compressed air,such as the high speed recision saw, the invention of the Wit iin namedand undersi ned applicant,now pending in the United tates Patent Office,Serial Number 614,425, Series 1915.

The undersigned inventor does not limit himself to the use of this valveto actuate the carriage of said saw machines, as it is working with highefiiciency upon air hoists, underground shovelling machines, ship remotecontrols, and generally in the automotive industrial field.

As exemplified in an air hoist, or any piston and cylinder mechanism,the present invention provides a remote control valve that permits oflocking the piston in any desired position with relation to its travelin the cylinder.

The present invention provides a sensitive control of the valve underequalization of high pressures.

This invent-ion relates to a system for the control of a mechanism inwhich is utilized a fluid cylinder and piston, and more particularly toan air brake system.

In such systems it has been customary to utilize the cylinder in such away that fluid pressure serves to move the piston in but one direction,and a spring or the like is used to move the piston in the otherdirection. This arrangement is unsatisfactory in many respects, due in agreat measure to the employment of a spring which necessarily involvesinefiicient mechanical arrangements. It is one of the objects of myinvention to provide a system havi ""r at mechanical complications andutilizing simple and inexpensive elements.

It is possible to attain these advantages by the aid of a novel controlvalve for the system. and it is another object of my invention toprovide such avalve. rendering it possible to utilize both sides of thecontrol cylinder for fluid pressure.

The invention possesses other advantageous features, some of which, withthe foregoing, will be set forth at length in the following description,where I shall outline in full that form of the invention which I haveselected for illustration in the drawings accompanying and forming partof'the present specification. In the drawings, I have shown but one formof my invention, but it is to be understood that I do not limit myselfto that form, since the invention as expressed in the claim, may beembodied in other forms as well.

Referring to the drawings:

Figure 1 is a view showing an air brake system embodying my invention.

Fig. 2 is a vertical sectional view of the control valve.

Fig. 3 is a top plan view of one of the parts making up the valvehousing, and serving'as the valve seat.

Fig. 4 is a bottom plan view of the rotatable valve member showing thegroove and the aperture which co-operate with the po" in the housing. r

Fig. 5 is a top plan view of a portion of the valve stem and of thevalve member, showing the mechanical connection between them, and c Fig.6 is a cross section of the valve member and the lower portion of thevalve stem, taken along line 6-6 of Fig. 5.

In the present instance my invention is shown as applied to an air brakesystem for vehicles, a portion only of the system being shown in Fig. 1.Here the brake rods 11 and 12 are pivotally connected to a link 13 atits ends. A relatively stationary pivot 14 is provided for the centralpoint of the link 13. A piston 15 is mechanically connected by its rod16 with one end of the link 13, as shown. This piston operates within acylinder 17. Pressure 1 applied to the piston 15 serves to move thebrake rods 11 and 12. and thus to apply or release the brakes. Althoughin the present instance an extremely simple and direct mechanicalarrangement of the parts is illustrated. it is to be understood thatother forms of brake mechanism may be used.

The control of the position of the piston is effected by admittingfluid, such as air, either to one or the other side of the piston 15within the cylinder. In this wav the piston may be moved from one end ofthe cylinder to the other, or retained in any intermediate position ifso desired. In order that the cylinder may function properly, it isnecessary to render it air tight, and this is efl'ected by properlysecuring the heads 18 and 19, and placing gaskets between it and thecylinder. An air tight gland 20 is also provided for permitting thepiston rod 16 to extend through the head 19. Leather rings 21 and 22 orthe like are locomotive.

fastened on each side of the piston to render the piston air tightwithin the cylinder.

In order to control the admission of the fluid to the cylinder, acontrol valve 23 is provided to which is connected the inlet pipe 24 andfrom which lead pipes 25 and 26. These pipes lead to opposite sides ofthe cylinder, as shown, and usually have considerable length, so thatthe control valve may be placed in any Convenient location for use bythe motor-man or the engineer oat a car or Furthermore, the same valve23 may be used to control the flow of air to a plurality of cylinderssuch as 17, simultaneously, and for this purpose branch pipes 27 and 28are illustrated.

The details of the control valve 23 are illustrated in Figs. 2, 3, 4, 5and 6. The movable valve parts are enclosed in a housing formed of a topmember 29, and a bottom member 30 which also serves as the valve seat.These two parts may be appropriately held together so as to form an airtight chamber, as by means of the bolts 31 and nuts 32. The inlet pipe24 has an extension or nipple 33 which is threaded into a taperedaperture in member 29 and serves to supply the valve chamber With thefluid under pressure. This valve chamber may preferably be cylindricaland so arranged as to accommodate the movable valve member 34 seated onthe inner surface of the bottom member 30. The contacting surfaces hereare accurately finished so as to provide a proper air tight seat. Themember 34 is adapted to be rotated by a valve stem 35 which extends downthrough a necklike extension of the housing member 29 This stem has anupper portion 36 which may be engaged by a handle 87 for turning thestem. This handle is shown as the conventional operating handle, and hasa projection 38 which fits underneath the flange 39 on member 29 andengageswith stops 40 at the limit of its movement in either di rection.

The mechanical connection between the stem and valve member 34 isefiected by means of a grooved boss or projection 41 preferably integralwith the member 34. This is most clearly shown in Fig. 6. The groove 42extends diametrically across the valve member 34, and into this grooveextendsthe boss or projection 43 formed i11- teg rally with the valvestem 35. The boss 41 has its central portion depressed slightly as shownmost clearly in the cross .section of Fig. 6, or in Fig. 5,and upon thisdepressed portion rests the enlarged end 44 of the valve stem 35. Thisend 44 is conical, as clearly shown in Fig. 2. A part of this bottomportion is cut away at an angle as shown at 45 so as to leave theport oraperture '46 uncovered. This port 46 extends entirely through the valvemember 34, and serves to allow the fluid under pressure to pass eitherinto pipe 25 or 26, or into neither, depending upon the relativeposition of this valve member with respect to the bottom member"30 ofthe housing.

For effecting these results, the bottom member 30 has a plurality ofapertures or ports, 47, 48 and 49, which extend into the enclosedchamber formed by the housing. Two of these ports, 48 and 49,communicate with the pipes and 26, and for this purpose they are tappedfrom below, at 50 and 51. Into these taps the pipes 25 and 26 arethreaded. The other port, 47, opens to atmosphere and serves to allowthe fluid under pressure to escape from either one or the other sides ofthe cylinder. In order to permit this exhaust to take place, the underside of the valve member 34 is provided as shown in Fig. 4, with a.circular slot which is long enough to connect either of the ports 48 or49 with the exhaust port 47. It is evident that by turning the valvemeniber34 in one or the other direction by the proper amount, thisconnection may be ettected. The port or aperture 46 is so situated withrespect to this slot 52 that while one of the ports 48 or 49 isconnected to exhaust port 47 by this slot, the other port is inalinement with the port 46. In this way fluid under pressure is suppliedto one side of the cylinder while the other side is exhausting. Thesectional view, Fig. 2, shows the port 46 in alinement with port 49, andport '48 connected to exhaust port 47.

It is also possible to place the valve member 34 in an intermediateposition with respect to ports 47, 48 and 49 so that the feed ports areselectively closed, whilst the exhaust port is always open to theatmosphere. This position corresponds to the superposing of Fig. 4 uponFig. 3; the aperture 46 would then fall between the ports 48 and 49. Insuch a position the air or fluid is held in both sides of the cylinder17, and the piston 15 is maintained in intermediate position. The stops40 on flange 39 are so located that the extreme movements of member 34in one or the other direction are just suthcient to connect either oneor the. other of ports 48 or 49 with the aperture 46, and the other portwith exhaust port 47.

It is to be noted that with the construction as shown, it is notnecessary to supply a spring or the like to maintain the valve member 34properly upon its seat. The pressure eirerted by the fluid in the valvechamber performs this function satisfactorily without the aid'o'tanyother elements. This feature contributes materially to the properoperation of the valve.

The mode of operation of the entire system may now be made plain. siredto maintain the piston 15 in any de- If it be desired position, thehandle b7 is turned to its neutral position, closing both ports 48 and49. Upon turning the handle in one direction as far as it will go, thefluid is allowed to escape from one side oi the piston, and fluid underpressure is :fed to the other side, with the result that the piston ismade to move either to the left or right. A movement of the valve handlein the other direction results in the movement of the piston in thereverse direction.

Although I have illustrated the control valve 23 as applied to an airbrake system, it is evident that it may be utilized in connection withother forms of mechanism where a double acting piston is needed.

I claim In a remote control system, a prime mover, a valve operablyconnected therewith, the said valve including a chamber having a seat, avalve having a port, mounted for rotary movement upon the seat betweenoppositely disposed fixed ports, and means to shift the. valve.

In testimony whereof, I have hereunto set my hand.

CHARLES F. ROBINSON.

